Cutting guide

ABSTRACT

A guide for use in cutting carpet and a method of joining two portions of cut carpet in edge-to-edge relationship has a base formed as a lower portion and an upper portion interengaged through a longitudinal slideway and presenting an upper ramp surface. The upper portion has a longitudinal channel along which a knife blade can pass to cut a carpet portion laid on the ramp. The lower portion has a vertical wall vertically below the channel and against which the cut edge of first carpet portion is located to abut during cutting of the second carpet portion on the ramp so that when the guide is removed the two cut edges will fall into edge-to-edge abutment for joining together.

The invention relates to a cutting guide and more particularly to acutting guide for use in making a cut in a flexible sheet member, suchas a carpet. The cutting guide is of especial value when a neat and tidyseam or joint is to be provided between two portions of carpet. Theinvention also extends to a method of using the guide.

BACKGROUND OF THE INVENTION

In my patent application PCT/GB 88/00805 Agents ref 2718 PCT, I havedescribed and claimed a guide for use in making a cut in a flexiblesheet member such as a carpet, the guide comprising a base having asubstanitally flat upper surface portion, an elongate channel to receivea cutting device such as the blade of a knife, extending adjacent theupper surface portion, the flexible sheet being arranged in use tooverlie the upper surface portion and the channel, wherein an inner sidewall of the channel extends at an oblique angle to the upper surfaceportion and the cutting device in use is urged towards that inner sidewall to produce a cut which is at an oblique angle to the plane of thesheet.

When the guide is used to form a seam between two portions of carpet,skill is required by the user to ensure that the cut edges are parallelto one another and are correctly spaced apart, so that when the guide isremoved, the cut edges fall together and abut each other.

It is one object of the invention to avoid or minimize that problem.

SUMMARY OF THE INVENTION

According to one aspect of the invention, there is provided a guide foruse in making a cut in two flexible sheet members such as carpets whichare to be placed in edge to edge contact, the guide comprising a basehaving a substantially flat upper surface portion, an elongate channelextending adjacent the upper surface portion to receive the blade of acutting device such as a knife, a side wall of the channel being at anoblique angle to the upper surface portion, wherein a substantiallyvertical wall portion extends longitudinally along the basesubstantially in vertical alignment with, and parallel to the mouth ofthe channel.

Preferably the base comprises an upper and a lower portion which includereleasable interengaging means so as to be movable relative to eachother in the direction of their length, the upper surface portion andthe channel are located on the upper base portion, and the vertical wallis located on the lower base portion.

In another aspect of the invention there is provided a method of joiningtwo portions of carpet or like sheet material in side-by-siderelationship comprising the steps of:

placing a guide according to the invention underneath the margin of thefirst portion of carpet;

inserting the blade of a knife in the channel and urging the bladetowards the oblique inner side wall while drawing the knife along thechannel;

discarding the marginal strip thereby provided;

turning the guide about 180° and placing the vertical wall portionadjacent the cut edge of the first carpet portion;

placing the margin of the second portion of carpet over the channel,inserting the blade therein, drawing it therealong and discarding themarginal strip thereby produced;

removing the guide and allowing or causing the two cut edges to falltogether;

adhering the cut edges to the floor or otherwise joining them together.

In this way, the lower base may be retained adjacent a cut edge of thefirst portion of carpet while the upper base portion is moved alongunderneath the second portion of carpet to thereby ensure that the cutedges always remain parallel to one another.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be better understood it will now bedescribed with reference to the accompanying diagrammatic drawings inwhich:

FIG. 1 is a perspective exploded view of a cutting guide of theinvention;

FIG. 2 is an end view of the guide of FIG. 1 at a stage of use; and

FIG. 3 is the same as FIG. 2 at a further stage of use.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIG. 1 a cutting guide comprises an elongate lower base portion 1having a substantially flat underside 2. One longer side of the lowerbase 1 defines a ramp portion 3 which is inclined upwardly from one sideedge 2A of the base 1. The opposing side of the base defines a verticalwall 4. The upper surface 5 of the base 1 is generally parallel to theunderside 2, but is formed with an integral rail 6 which extends alongthe length of the base 1 and is generally of a broad "T"-shape incross-section. The end face 7 of the lower base 1 may includeinterlocking lugs (not shown), whereby a plurality of such bases 1 maybe placed in end-to-end relation, so as to extend the length of thetrack 6.

An elongate upper guide portion 8 overlies the lower base portion 1 andhas a substantially flat underside 9 including a slot 10 which is of agenerally "T"-shaped section and which is complementary to the rail 6 onthe lower base 1. The upper portion 8 includes a side ramp portion 11 onthe upper surface which is inclined upwardly from one side. A channel 12extends along the base 8, at the top of the ramp 11 parallel to the edge2A. The channel 12 includes an inner side wall 13 which is inclined atan oblique angle to the adjacent ramp portion 11. The upper and lowerbase portions 1, 8 are dimensioned so that when the rail 6 is receivedin the slot 10 to form a longitudinal slideway, the vertical wallportion 4 lies "vertically" (see the comments herein after) below themouth of the channel 12 with which it is parallel. The upper surface 14of the upper base 8 beyond the channel 12 is horizontal and ends in avertical side wall 15. The side wall 15 defines an inwardly extending"T"-shaped slot 16 to receive a complimentary "T"-shaped extension 17 ofa stop 18 or upstanding side wall which extends above the level of theupper surface 14. Each base portion 1, 8 may be formed as an extrusionfrom aluminium or like alloy, or may be formed from plastics material.

In use of the guide, the upper portion 8 is slid into position above thelower base 1 and the stop 18 is fixed in the slot 16. The guide is thenplaced underneath the margin of the first piece of carpet 20 to bejoined, with the free edge in contact with the stop 18. The blade of aknife 21 is inserted in the channel 12 and urged towards the obliqueside wall 13. The knife 21 is drawn along the channel 12 to cut off themargin of the carpet 20. In the case where a plurality of lower bases 1are joined end to end, the upper base 8 may be periodically moved alongthe slideway formed between the 6 and slot 10 and relative to the lowerbase 1, as the cut is made. The margin is then discarded. The guide isthen turned about through 180°, to the condition shown in FIG. 3, andthe vertical wall 4 placed against the cut edge 22 of the first portionof the carpet 20. The second portion 23 of the carpet to be joined isthen lain over the channel 11 with the edge thereof in contact with thestop 18. The blade of the knife is then inserted in the channel anddrawn therealong as before, to produce a cut edge 24. The margin therebyproduced is discarded. Because the vertical wall 4 is "vertically" (seebelow) beneath the mouth of the channel 12, once the guide has beenremoved, the two cut edges 22, 24 fall together in abutting edge to edgecontact. It will be appreciated from the foregoing that for the two cutedges 22 and 24 to fall together in abutting edge to edge contact, thelength of the carpet 23 extending over the ramped surfaces 3 and 11 toits cut edge 24 should substantially correspond to the width of theunderside 2 of the base portion 1. Consequently to allow for the ramps 3and 11, the mouth of the channel 12 will be offset from verticalalignment with the wall 4 and located slightly closer (in a horizontalplane) to the longitudinal edge 2A formed between the ramp 3 andunderside surface 2 then the horizontal spacing between thatlongitudinal edge 2A and the wall 4. In practice this difference inhorizontal spacing is likely to be extremely small so that the mouth ofthe channel 12 may be considered as being substantially in verticalalignment with the wall 4; for example in a practical embodiment theoverall height of the base 1 and guide portion 8 (fitted thereto throughthe slideway) may be 13 millimeters with the ramps 3 and 11 subtendingan angle of approximately 20° with the underside face 2 and for the cutcarpet portions to fall together with their edges 22 and 24 in abutment,the mouth of the channel 12 may be offset as aforementioned byapproximately 1.5 millimeters out of absolute vertical alignment withthe wall 4. Consequently the spacing from the edge 2A over the profileof the ramped surfaces 3 and 11 to the channel 12 is substantially thesame as the spacing from the edge 2A over the flat underside surface 2to the vertical wall 4. The two cut edges 22, 24 may be adhered to thefloor or otherwise attached together.

The invention is not limited to the embodiment shown. For example, thecutting device may be integrally formed with the base.

I claim:
 1. A method of joining two flexible sheet members inside-by-side relationship by providing a guide which has a basecomprising an upper base portion and a lower base portion and asubstantially flat underside surface on the lower base portion, thelower base portion having a longitudinally extending wall which isspaced from and parallel with a longitudinally extending edge of saidunderside surface and which wall, when said underside surface ishorizontal, extends upwardly from the underside surface, the base havingan upper surface portion which overlies the underside surface andpresents a ramp that extends from said edge of the underside surface andsubtends an acute angle with said underside surface, the upper surfaceportion having a longitudinally extending cutting guide edge whichextends parallel to said wall and is formed by a channel in the upperbase portion, the wall being spaced from said edge of the undersidesurface over the underside surface substantially the same distance asthe guide cutting edge is spaced over the upper surface portion fromsaid edge of the underside surface, and the upper base portion beingmovable relative to the lower base portion in the longitudinallydirection of the channel, and wherein the method comprises placing saidguide underneath a margin of a first said sheet member such that saidfirst sheet member to lies on the upper surface portion over the channelin the upper base portion; inserting a knife blade in said channel anddrawing the blade along the guide edge of the channel to provide a cutedge to said first sheet member, moving the upper base portion relativeto the lower base portion in the longitudinal direction of the channelto translate the channel and guide edge beneath the first sheet memberand drawing the knife blade along the so translated guide edge to extendsaid cut edge to the first sheet member and discarding a marginal stripcut from said first sheet member; turning the guide about 180° andplacing said upstanding wall that extends from the underside surfaceadjacent to said cut edge of the first sheet member; placing a margin ofa second said sheet member to lie on the upper surface portion over thechannel and inserting said knife blade in the channel and drawing theblade along the guide edge of the channel to provide a cut edge for saidsecond sheet member, moving the upper base portion relative to the lowerbase portion in the longitudinal direction of the channel to translatethe channel and guide edge beneath the second sheet member and drawingthe knife blade along the so translated guide edge to extend said edgeto the second sheet member and discarding a marginal strip cut from saidsecond sheet member, and removing the guide so said cut edges of thefirst and second sheet members move into edge-to-edge contact.
 2. Aguide for use in making a cut in a flexible sheet member to form an edgeof said member for two of said members to be placed in side-by-side andedge-to-edge contact relationship, said guide comprising a base havingan upper base portion and a lower base portion and a substantially flatunderside surface on the lower base portion; said lower base portionhaving a longitudinally extending wall which is spaced from and parallelwith a longitudinally extending edge of said underside surface, saidwall extending upwardly from said underside surface; said upper baseportion having an upper surface portion which overlies the undersidesurface and defines a ramp that extends from said edge of the undersidesurface and subtends an acute angle with said underside surface, saidupper surface portion defining a longitudinally extending cutting guideedge that extends parallel to said wall, said cutting guide edge definedby a channel in the upper base portion; said wall being spaced from saidedge of the underside surface over said underside surface substantiallyby the same distance as the cutting guide edge is spaced over the uppersurface portion from said edge of the underside surface, whereby with anedge of a first said sheet member abutting said wall, a second saidsheet member laid on the upper surface portion to overlay the channelhas an edge cut along said cutting guide edge by a knife blade receivedwithin and moving longitudinally along said channel so that when theguide is removed the said edges of the first and second sheet member layflat and in edge-to-edge contact, and said upper base portion beingmovable longitudinally relative to the lower base portion to therebyextend the length of a cut which is formed in the sheet member along thecutting guide edge.
 3. A guide as claimed in claim 2 in which thecutting guide edge is defined by a side wall of the channel whichchannel side wall is located adjacent to the upper surface portion andis inclined at an oblique angle relative thereto.
 4. A guide as claimedin claim 2 further comprising a side wall stop surface providedupstanding from the upper surface portion and spaced from and parallelwith the cutting guide edge and against which an edge of a said sheetmember laying on the upper surface portion abuts during cutting thereof.5. A guide as claimed in claim 4 in which said side wall stop surfaceupstanding from the upper surface portion is removably attached to theupper base portion.
 6. A guide as claimed in claim 2 wherein slidewaymeans is provided between said upper and lower base portions for saidbase portions to be slidably movable longitudinally relative to eachother.
 7. A guide as claimed in claim 2 in which the upper base portionis releasably engaged with the lower base portion.